Kicking the Habit

The latest smoking-cessation drug, Varenicline, could offer a more effective alternative to the popular antidepressant Zyban. Varenicline attaches to nicotine receptors in the brain, blocking nicotine from binding to them and producing a buzz, but stimulating them just enough to reduce withdrawal. In two studies, 44 percent of smokers treated with it for 12 weeks quit completely during this period, compared with 30 percent of subjects who took Zyban and 18 percent of those given a placebo. Half of those who quit resumed smoking within a year, but Varenicline still had the best track record. Although some people who took the drug experienced mild nausea and vivid dreams, few backed out of the study because of this, says researcher Serena Tonstad of the University of Oslo. Varenicline could be available by prescription near the end of the year.